Safety-clamp for drill-rods and the like.



0. WOMM ER.

SAFETY CLAMP FOR DRILL RODS AND THE LIKE.

APPLIGATION FILED NOV. 6, 1911,

Patented Aug. 20, 1912.

COLUMBIA PLANDOEAFH 00.. wAsl-IlNu'mN, D. c.

ATENT orr'ron.

SAFETY-CLAMP FOR DRILL-RODS AND THE LIKE.

Specification of Letters Patent.

Patented Aug. 20, 1912.

Application filed November 6, 1911. Serial No. 658,800

To all whom it may concern:

Be it known that I, CHARLES WoMMnR, a citizen of the United States,residing at Mammoth, in the county of Shasta and State of California,have invented new and useful Improvements in Safety-Clamps forDrill-Rods and the Like, of which the following is a specification.

This invention relates to drilling apparatus and particularly to a clampfor the same.

The object of the present invention is to provide an extremely simple,powerful, easily operated, adjustable clamping device adapted to supportthe weight of one or more sections of drill bars, tubes, sleeves or thelike; and particularly to provide a drill bar or tube clamp adaptablefor use in drilling machinery of such nature wherein the drill bars orrods are occasionally vertically lifted from the hole being drilled andsuspended in vertical lifted position while connections ordisconnections are being made.

An important object of the present invention is to design a safety clampfor drill rods, which will automatically lock and unlock itself relativeto the drill bars, and which clamp may be readily and manually releasedfrom the bars when necessary.

It is also an important object to provide such a safety clamp as willinsure the prevention of the rotation of the drill bars or pipes, whenforce is applied to the latter for connection or disconnection ofadditional sections or for other reasons.

The invention consists of the parts and the construction and combinationof parts, as hereinafter more fully described and claimed, havingreference to the accompanying drawings, in which Figure 1 is aperspective view of the safety clamp as adapted for use. Fig. 2 is aplan view of the clamp. Fig. 8 is a side elevation in partial section.Fig. 4: is a detail view of the faces of the clamping jaws. Fig. 5 is anend view of the clamps.

In the use of certain classes of drilling apparatus commonly known asdiamond drills, it is common to employ a series of rods or pipesconnected in sections, whereby the cutting head of the tool may becontinued down so as to permit the drilling of very deep holes. In theoperation of this kind of drill, the operators have frequently to couplethe additional sections of rod or plpe, as 2, Fig. 1, as the drillingoperation proceeds, and it is also frequently necessary to withdraw theassembled drilling rods for the removal of cores from the drills and forother purposes. IVhen such removal is necessary the lowermost sectionsof the rods which are coupled must be supported within the hole whilethe uppermost section is disconnected, as by unscrewing, which is acommon method of connection.

It is a desideratum to provide a simple, powerful, and reliable clampcapable of sustaining the load of numerous coupled sections of drillingbars or rods 2, while the uppermost rod is being disconnected. To thatend the present clamp comprises a number of elements cooperative toautomatically lock themselves upon the exterior surface of a drill rodwith such a degree of firmness and security that the lower sections willbe sustained in an elevated position and the section which is embracedby the clamp will be positively prevented from rotation while a suitabletool is applied to the uppermost section for its removal.

'I have found by actual use for a long pe riod of time that the deviceherein described fully and satisfactorily accomplishes these severalpurposes.

In the illustration, the device is shown as comprising oppositelydisposed jaws 3-4, which may be substantially polygonal or rectangularin form. Each of the jaws have one face recessed and provided with anumber of teeth 5-6 respectively. The jaws 34 are independently slidablebetween side plates 7 of suitable proportions and dimensions, which aresecurely fastened together by means of suitable shouldered bolts orother equivalent devices 8, having nuts 9 which may be readily removedfrom the bolts so that the device can be quickly assembled anddisassembled in operation.

The clamp jaws 3- 1: are prevented from vertical movement between theside plates 7 by suitable guides 10 which project sufficiently on thesides of the plates 7 to limit the up or down movement of the clampjaws. Bookable upon the spacing bolts 8, which secure the plates 7 inproper relation, are

the levers 11 of suitable design and proportion, having formed upon oneend a cam or bearing surface, as 12, of such contour as to frictionallybind upon and lock the jaws 3-4l upon the surface of a drill section 2,as clearly shown.

Preferably the depth of the depressed portion in which the teeth 56 areprovided'is such that the two faces of the jaws 34 will not come intocontact. In other words, the diameter of the drill section 2 will besuflicient to effectually spread the jaws 34 When the clamp has beenarranged in position about a drill section, with the levers 11 fulcrumedupon any suitable and convenient support, as for instance, the timbers13, then, when the drill section 2 is to be clamped, the levers 11 swingdownwardly upon their fulcrums 13, so that the cam faces 12 will beforced against the adjacent sides of the jaws 34 with such force as topress the latter toward each other, thereby causing the drill section 2to be embraced by the teeth 56 of the jaws.

If the operator desires to temporarily release the drill section 2 fromthe clutch of the jaws 34, a pressure on the outermost end of either oneof the levers 11 will sufiiciently lift the inner end of that particularlever, so that its cam face 12 will be relieved of pressure against theadjacent jaw, as 4, and the drill rod 2 released. It will thus be seenthat during the normal driving operation of the drill body or section 2it is desired to release it from the control of the jaws 34, so as topermit the ready and free rotation of the drill bit, as is usual indiamond drills, and during such rotation the clamp may be entirelydisconnected, if desired by removing the nuts 9 from the screws, andthus allowing the clamp to be disassembled; or the pressure of theclutch jaws 3-4 may be removed by the release of one of the jaws frompressure of the adjacent cam face of a lever 11 by pressing this leverdownwardly.

hen the drill sections are to be uncoupled, it is necessary to withdrawor lift the assembled drilling tool slightly so that the uppermostsection will project sufliciently above the surface of the ground, as inFig. 1, to permit the application of a suitable tool to unscrew thelatter from the next lower section, which is in control of and clampedby the jaws 34 of the clamp, when the latter is assembled, as shown. Itwill be seen that as soon as a drill has been slightly lifted and theclamp assembled about it, and the latter is supported upon the fulcrums13, when the drill is released and slightly lowered, it will be firmlyembraced between the jaws 3-4, as the fulcrums 8 of the levers rocktoward each other and press the cam faces against the clamp jaws.

The heavier the train of drill rods, the greater is the force which willbe exerted by the levers 11 to force the jaws 3-4 against the drillsection.

One of the important features of my invention is in so designing thejaws 3-4: that they will effectually hold the drill not only in elevatedposition, but also against turning within the clamp when power isapplied to the uppermost section of the drill to unscrew it from thenext section. To that end I have found that this is effectuallyaccomplished by forming the teeth 56 in the jaws 3 1 at oppositeinclination or pitch, as clearly shown in Fig. fl. That is, that insteadof forming the teeth in each jaw with the edge lines parallel to theends of the jaw, I prefer to pitch the teeth, as is common in screwthreads, pitching the teeth in one jaw as like a right hand thread andpitching the teeth of the other jaw as like a left hand thread. When thetwo jaws are assembled face to face, these teeth being of oppositepitch, will effectually bind upon the surface of the drill section, andbeing oppositely pitched will each resist any turning inclination of thedrill. This designI have found to be extremely efficient in actualpractice and it obviates the requirement of two tools or other deviceswhich are commonly employed. By the present clamp the operator simplyapplies one tool to the drill section to be removed, thereby unscrewingthis section without imparting any turning motion to the lower sectionsand without using any other tool to restrain the turning mot-ion of thelowermost sections since they are positively prevented from rotation ineither direction by the oppositely pitched teeth 5(3 of the clamp aws.

Having thus described my invention, what I claim and desire to secure byLetters Patent is- 1. A clamp for suspending a cylindrical body,comprising a pair of movable toothed jaws adapted to embrace the body, aguide structure in which the jaws are movable, said structure havingflanges projecting inwardly .above and below the jaws and confining saidjaws therebetween and levers pivoted in the structure and having facesoperative against the jaws.

2. A clamp for suspending and preventing revolution of a cylindricalbody, comprising a jaw structure having transversely oppositely pitchedhelical teeth in adjacent faces, adapted to embrace the body, a supportin which the jaws are mounted, said support having top and bottomflanges between which the jawsare confined against lengthwise movement,and cam-levers pivoted in the structure and adapted to close the jaws onthe body.

3. A drill clamp comprising a body structure having side plates with topand bot- In testimony whereof I have hereunto set tom flanges adapted toembrace a drill seomy hand in the presence of two subscrlbing tio-ntherebetween, a peir of movable toothed Witnesses.

jaws and cam-levers plvoted upon the struc- CHARLES WOMMER. 5 ture andadapted to close the jaws when Witnesses:

the former are rested upon said bottom MANUEL PERRY,

flanges. A. L. DOFFLEMYER.

Gopies of this patent may be obtained for five cents each, by addressingthe Commissioner of .Patents, Washington. D. 0.

